There are many requirements for high efficiency, low contact loss, compact resistive heaters, such as, sources of infrared radiation, various heating applications, and ignitors for gas appliances, such as, stoves and driers. Such resistive heaters are basically a section of uniform resistance material having connection means at the ends thereof for applying electrical power. These heaters are problemsome from many points of view.
At high heater operating temperatures the heater ends become too hot to make stable electrical connections thereto. Also, in certain applications where there is a large amount of moving air near the emitter much of the heat is drawn away from the heating elements by convection. In the past the heating elements have been put in protective tubes to protect against such convection heat loss. However, because of the difference in expansion and contraction of the materials making up the heating element and the protective tube, it has been somewhat difficult to mechanically couple the two for providing a compact unit.